Successful treatment with rituximab and plasmapheresis of renal involvement of eosinophilic granulomatosis with polyangiitis

Background Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare disorder characterized by asthma, eosinophilia, and systemic vasculitis. Renal involvement is not regarded as a prominent feature and the treatment is still under study. Case presentation A 68-year-old woman was admitted to our hospital because of fever, renal dysfunction, eosinophilia, and the presence of MPO-ANCA. Based on the renal pathological examination which showed extravascular eosinophilic-predominant inflammation and crescentic glomerulonephritis, EGPA was diagnosed. Considering the acute kidney injury, prominent eosinophilia, and strongly positive anti-MPO antibodies, pulse steroid therapy was administered, followed by intravenous rituximab. Plasmapheresis was also provided (9 sessions). The eosinophil count was normalized, and renal dysfunction was reversed. The patient no longer requires dialysis. Conclusions Renal involvement of EGPA is rare, and consensus on its treatment is still lacking, because of a lack of large-scale randomized controlled trials. We treated our patient as a case with high severity. For patients with severe disease, the addition of cyclophosphamide to glucocorticoid therapy is commonly used. However, rituximab and plasmapheresis combined with systemic glucocorticoid therapy were found to be beneficial because the renal function and other clinical conditions were almost fully recovered. Thus, our treatment is highly effective against renal involvement of eosinophilic granulomatosis with polyangiitis. Keywords: Eosinophilic granulomatosis with polyangiitis, Renal involvement, Rituximab, Plasmapheresis